Objective: To make a further understanding of the DSA features of the carotid body tumor (CBT) and to explore the clinical value of DSA diagnosis and interventional treatment for CBT. Methods: Twelve cases of CBT with...Objective: To make a further understanding of the DSA features of the carotid body tumor (CBT) and to explore the clinical value of DSA diagnosis and interventional treatment for CBT. Methods: Twelve cases of CBT with DSA data were analyzed retrospectively. The DSA appearances in all of the patients were observed dynamically in a double blind manner by two experienced radiologists together and a consensus interpretation formed. Results: DSA could establish definitive diagnosis in all cases. The DSA features of the CBT were: the increase of bifurcation angles of internal and external carotid arteries in all cases; the CBT supplied by external carotid arteries in most cases and the significant increase of tumor vessels in bifurcation; invasion of internal or external carotid arteries in 6 cases. The tumor staining disappeared mostly after the supplying arteris were embolized in 2 cases, and the bleeding during the operation reduced significantly. Conclusion: The DSA is useful in the diagnosis of the CBT and for therapeutic planning. The pre-operation embolization of the CBT contributes to reduce the bleeding during operation.展开更多
Previous studies emphasize the important role of a "north-ridge versus south-trough" dipole (affecting the latitudes from 20° to 75° N around the Tibetan Plateau) of anomalous geopotential height (...Previous studies emphasize the important role of a "north-ridge versus south-trough" dipole (affecting the latitudes from 20° to 75° N around the Tibetan Plateau) of anomalous geopotential height ( Z ) in the early-2008 abnormal cryogenic freezing-rain-and-snow events in the southern part of China. The present study intends to extract the leading signal facilitating the dipole based on the numerical outputs of a full Z-linear model for diagnosing the global Z . Using this model built on full primitive equations in spherical-isobaric coordinates, we can further split the anomaly of Z-Zfζ-uβ (representing the Z component not explicitly associated with the Coriolis parameter f and its meridional derivative β ) into 15 components. With the model-output Zfζ-uβ (mainly accounting for the dipole under the geostrophic balance) and Z-Zfζ-uβ matrices as the left and right singular vectors respectively, a maximum covariance analysis (MCA) is performed to extract the significant 2-4-day leading signal carried by the MCA Z-Zfζ-uβ mode in the upstream area of the dipole. This leading signal is mainly attributed to 1) the abnormally strong westerlies centered around the exit region of the Atlantic jet-stream and 2) the corresponding anomalous 950-300 hPa anticyclone to the south of the abnormally strong center of westerlies. The energy of the positive wave center around this jet exit region favors the downstream north-ridge while the energy of the negative wave center associated with the anomalous anticyclone favors the downstream south-trough.展开更多
The design of a segmented-rod projectile is often simplified into an ideal one in theoreti-cal analysis for the convenience of modeling of its performance.But the actual performance of non-ideal segmented-rod projecti...The design of a segmented-rod projectile is often simplified into an ideal one in theoreti-cal analysis for the convenience of modeling of its performance.But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored.AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities,which can be used to guide the optimal design of weaponry segmented-rod projectiles.展开更多
Objective To evaluate and reduce inter-observer variations in the detection and characterization of pulmonary nodules on digital radiograph （DR） chest images. Methods Two hundreds and thirty-two new posterior-anteri...Objective To evaluate and reduce inter-observer variations in the detection and characterization of pulmonary nodules on digital radiograph （DR） chest images. Methods Two hundreds and thirty-two new posterior-anterior DR chest images were collected from out-patient screening patients. Consensus was reached by two experienced radiologists on the marking, rating, and segmentation of small actionable nodules ranged from 5 to 15 mm in diameter using a computer-aided diagnosis （CAD） system. Both their own nodule findings and the computer＇s automatic nodule detection results were analyzed to make the consensus. Nodules identified together with corresponding likelihood rating and segmentation results were referred as ＂Gold Stand- ard＂. Two un-experienced radiologists were asked to first mark and characterize suspicious nodules independently, then were allowed to consult the computer nodule detection results and change their decisions. Results Large inter-observer variations in pulmonary nodule identification and characterization on DR chest images were observed between un-experienced radiologists. Un-expefienced radiologists could greatly benefit from the CAD system, including substantial decrease of inter-observer variation and improvement of nodule detection rates. Moreover, radiologists with different levels of skillfulness could achieve similar high level performance after using the CAD system. Conclusion The CAD system shows a high potential for providing a valuable assistance to the examination of DR chest images.展开更多
Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter＇s original sample and five groups of duplication samples, which have three kinds of moistu...Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter＇s original sample and five groups of duplication samples, which have three kinds of moisture. The results of those tests indicate that confining pressure effect, structure effect and moisture effect all have influence to fault matter＇s nature. Meanwhile, the distortion destruction and stability variation of fault crush zone are the main reason which causes water-inrush lag-effect. Simultaneously, the stimulation computation we made by the numerical simulation software FLAC 3D also describes the mining influence to floor strata, fault crush zone＇s range and size, the influence of confined water on overburden and the fault zones, also it describes the time effect of bearing influenced by confined water and the rock dank height of confined water along the fault zones influenced by the specific water head.展开更多
Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using lar...Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using large finite element soft-ANSYS and element birth-death method. The results show that the more high the underground water pressure, the more big the floor displacement and possibility of water-inrush; the floor which has fault structure is more prone to water-inrush than the floor which not has fault structure, the floor which has multi-groups cracks is more prone to water-inrush than the floor which has single-group cracks. The numerical simulation result forecasts the water-inrush in working face preferably.展开更多
Acute pulmonary embolism(APE) in operation room is a constant,lethal but treatable disease.A fast determination of APE in an operation room is currently difficult due to a non-specificity on its signs,symptoms,electro...Acute pulmonary embolism(APE) in operation room is a constant,lethal but treatable disease.A fast determination of APE in an operation room is currently difficult due to a non-specificity on its signs,symptoms,electrocardiograph findings,arterial blood gas abnormalities and chest X-rays.Clinically,an APE can automatically originate from a small and clinically asymptomatic embolus to massive,proximal emboli with shock during a scheduled surgery period.An accurate,brief and prompt diagnostic and therapeutic strategy for APE in a peri-operation period is crucial for anesthesiologists to make a decision on an appropriate clinical intervention to improve patients' outcomes.The purpose of this mini-review article is to illuminate a fast-track diagnostic and therapeutic strategy for APE patients in a perioperative period through a hybrid of the high sensitive and high specific viable diagnostic modality of D-dimer assay in conjunction with necessary emergent pulmonary angiography(EPA),including digital subtraction angiography(DSA),or a spiral computed tomography angiography(sCTA) for APE patients' diagnosis and treatment during operation.The postulated fast-track diagnostic and therapeutic strategy can effectively confirm or exclude highly suspected APE and simultaneously provide fast therapeutic opportunities for APE patients at an operative period.展开更多
In order to study the influence of a fault on the movement law of the overlying strata as well as its effect on the gas drainage boreholes, based on the practical situation of 1242（1） panel at Xieqiao Mine in Huaina...In order to study the influence of a fault on the movement law of the overlying strata as well as its effect on the gas drainage boreholes, based on the practical situation of 1242（1） panel at Xieqiao Mine in Huainan, the Finite Element Method （FEM） model was built up, and the distribution of the stress field and the displacement field of the overlying strata in the stope with a fault were simulated by using the FEM software ANSYS. The results indicate that because of the existence of the fault, the horizontal displacement of overlying strata near the gas drainage borehole becomes larger than that in the stope without a fault, and the distribution of the stress field of the overlying strata changes greatly. When the working face is far away from the fault, the distribution of the stress field is approximately symmetrical. As the working face advances to the place 50 m away from the fault, the stress range at the right side goaf area is as twice as that at the left side. Here, the stress distribution area of goaf area and the fault plane run through, the fracture-connected-zone is formed. It can be presumed that the gas adsorbed in the coal and rock will flow into the fault zone along the fracture-connected-zone, which causes the quantity of gas drainage reduce remarkably.展开更多
The Anqing MS4.8 earthquake occurred on January 19, 2011, with the epicenter lying in the foreland deformation belt along the Yangtze River of the lower Yangtze block. After the earthquake, the field work team surveye...The Anqing MS4.8 earthquake occurred on January 19, 2011, with the epicenter lying in the foreland deformation belt along the Yangtze River of the lower Yangtze block. After the earthquake, the field work team surveyed and collected building damage data, calculating and obtaining more accurate intensity distributions. The focal mechanism of the main shock was calculated tentatively using digital seismic wave data from provincial digital seismic networks using the FOCMEC program and the first motions of P, SV and SH waves with their amplitude ratios. Using the location results of the main shock and aftershocks by the Anhui seismic network, combining the three-dimensional crust velocity structure imaging results of the focal region by seismic tomography, and referring on intensity distribution of the elliptic major axis' predominant direction, we conclude by comprehensive analysis that the NE-trending Susong-Zongyang fault is possibly the causative fault of the Anqing earthquake.展开更多
文摘Objective: To make a further understanding of the DSA features of the carotid body tumor (CBT) and to explore the clinical value of DSA diagnosis and interventional treatment for CBT. Methods: Twelve cases of CBT with DSA data were analyzed retrospectively. The DSA appearances in all of the patients were observed dynamically in a double blind manner by two experienced radiologists together and a consensus interpretation formed. Results: DSA could establish definitive diagnosis in all cases. The DSA features of the CBT were: the increase of bifurcation angles of internal and external carotid arteries in all cases; the CBT supplied by external carotid arteries in most cases and the significant increase of tumor vessels in bifurcation; invasion of internal or external carotid arteries in 6 cases. The tumor staining disappeared mostly after the supplying arteris were embolized in 2 cases, and the bleeding during the operation reduced significantly. Conclusion: The DSA is useful in the diagnosis of the CBT and for therapeutic planning. The pre-operation embolization of the CBT contributes to reduce the bleeding during operation.
基金National Key Basic Research Project of China (2009CB421404)a key project of Chinese National Science Foundation (40930950+2 种基金 40730951)Chinese National Science Foundation (40575021)General Program of CAFUC (J2010-29)
文摘Previous studies emphasize the important role of a "north-ridge versus south-trough" dipole (affecting the latitudes from 20° to 75° N around the Tibetan Plateau) of anomalous geopotential height ( Z ) in the early-2008 abnormal cryogenic freezing-rain-and-snow events in the southern part of China. The present study intends to extract the leading signal facilitating the dipole based on the numerical outputs of a full Z-linear model for diagnosing the global Z . Using this model built on full primitive equations in spherical-isobaric coordinates, we can further split the anomaly of Z-Zfζ-uβ (representing the Z component not explicitly associated with the Coriolis parameter f and its meridional derivative β ) into 15 components. With the model-output Zfζ-uβ (mainly accounting for the dipole under the geostrophic balance) and Z-Zfζ-uβ matrices as the left and right singular vectors respectively, a maximum covariance analysis (MCA) is performed to extract the significant 2-4-day leading signal carried by the MCA Z-Zfζ-uβ mode in the upstream area of the dipole. This leading signal is mainly attributed to 1) the abnormally strong westerlies centered around the exit region of the Atlantic jet-stream and 2) the corresponding anomalous 950-300 hPa anticyclone to the south of the abnormally strong center of westerlies. The energy of the positive wave center around this jet exit region favors the downstream north-ridge while the energy of the negative wave center associated with the anomalous anticyclone favors the downstream south-trough.
文摘The design of a segmented-rod projectile is often simplified into an ideal one in theoreti-cal analysis for the convenience of modeling of its performance.But the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely explored.AUTODYN numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities,which can be used to guide the optimal design of weaponry segmented-rod projectiles.
文摘Objective To evaluate and reduce inter-observer variations in the detection and characterization of pulmonary nodules on digital radiograph （DR） chest images. Methods Two hundreds and thirty-two new posterior-anterior DR chest images were collected from out-patient screening patients. Consensus was reached by two experienced radiologists on the marking, rating, and segmentation of small actionable nodules ranged from 5 to 15 mm in diameter using a computer-aided diagnosis （CAD） system. Both their own nodule findings and the computer＇s automatic nodule detection results were analyzed to make the consensus. Nodules identified together with corresponding likelihood rating and segmentation results were referred as ＂Gold Stand- ard＂. Two un-experienced radiologists were asked to first mark and characterize suspicious nodules independently, then were allowed to consult the computer nodule detection results and change their decisions. Results Large inter-observer variations in pulmonary nodule identification and characterization on DR chest images were observed between un-experienced radiologists. Un-expefienced radiologists could greatly benefit from the CAD system, including substantial decrease of inter-observer variation and improvement of nodule detection rates. Moreover, radiologists with different levels of skillfulness could achieve similar high level performance after using the CAD system. Conclusion The CAD system shows a high potential for providing a valuable assistance to the examination of DR chest images.
文摘Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter＇s original sample and five groups of duplication samples, which have three kinds of moisture. The results of those tests indicate that confining pressure effect, structure effect and moisture effect all have influence to fault matter＇s nature. Meanwhile, the distortion destruction and stability variation of fault crush zone are the main reason which causes water-inrush lag-effect. Simultaneously, the stimulation computation we made by the numerical simulation software FLAC 3D also describes the mining influence to floor strata, fault crush zone＇s range and size, the influence of confined water on overburden and the fault zones, also it describes the time effect of bearing influenced by confined water and the rock dank height of confined water along the fault zones influenced by the specific water head.
文摘Used numerical simulation method to study the floor water-inrush mechanism in working face which was influenced by fault structure, and set up many kinds of models and performs numerical calculation by fully using large finite element soft-ANSYS and element birth-death method. The results show that the more high the underground water pressure, the more big the floor displacement and possibility of water-inrush; the floor which has fault structure is more prone to water-inrush than the floor which not has fault structure, the floor which has multi-groups cracks is more prone to water-inrush than the floor which has single-group cracks. The numerical simulation result forecasts the water-inrush in working face preferably.
文摘Acute pulmonary embolism(APE) in operation room is a constant,lethal but treatable disease.A fast determination of APE in an operation room is currently difficult due to a non-specificity on its signs,symptoms,electrocardiograph findings,arterial blood gas abnormalities and chest X-rays.Clinically,an APE can automatically originate from a small and clinically asymptomatic embolus to massive,proximal emboli with shock during a scheduled surgery period.An accurate,brief and prompt diagnostic and therapeutic strategy for APE in a peri-operation period is crucial for anesthesiologists to make a decision on an appropriate clinical intervention to improve patients' outcomes.The purpose of this mini-review article is to illuminate a fast-track diagnostic and therapeutic strategy for APE patients in a perioperative period through a hybrid of the high sensitive and high specific viable diagnostic modality of D-dimer assay in conjunction with necessary emergent pulmonary angiography(EPA),including digital subtraction angiography(DSA),or a spiral computed tomography angiography(sCTA) for APE patients' diagnosis and treatment during operation.The postulated fast-track diagnostic and therapeutic strategy can effectively confirm or exclude highly suspected APE and simultaneously provide fast therapeutic opportunities for APE patients at an operative period.
基金Supported by the National Natural Science Foundation of China（50534080） the National Basic Research Program of China（2005CB221504） Taishan Scholar Engineering Construction Foundation of Shandong Province
文摘In order to study the influence of a fault on the movement law of the overlying strata as well as its effect on the gas drainage boreholes, based on the practical situation of 1242（1） panel at Xieqiao Mine in Huainan, the Finite Element Method （FEM） model was built up, and the distribution of the stress field and the displacement field of the overlying strata in the stope with a fault were simulated by using the FEM software ANSYS. The results indicate that because of the existence of the fault, the horizontal displacement of overlying strata near the gas drainage borehole becomes larger than that in the stope without a fault, and the distribution of the stress field of the overlying strata changes greatly. When the working face is far away from the fault, the distribution of the stress field is approximately symmetrical. As the working face advances to the place 50 m away from the fault, the stress range at the right side goaf area is as twice as that at the left side. Here, the stress distribution area of goaf area and the fault plane run through, the fracture-connected-zone is formed. It can be presumed that the gas adsorbed in the coal and rock will flow into the fault zone along the fracture-connected-zone, which causes the quantity of gas drainage reduce remarkably.
基金funded by the Key Research Program of "Tracking the Southern Section of the Tancheng-Lujiang Fault Zone and Study on the Earthquake Risk in Its Vicinity among 2011 National Seismic Risk Zones " (2011013301)the Youth Projects of Earthquake Research Fund of Anhui Province,2011 (20110403)
文摘The Anqing MS4.8 earthquake occurred on January 19, 2011, with the epicenter lying in the foreland deformation belt along the Yangtze River of the lower Yangtze block. After the earthquake, the field work team surveyed and collected building damage data, calculating and obtaining more accurate intensity distributions. The focal mechanism of the main shock was calculated tentatively using digital seismic wave data from provincial digital seismic networks using the FOCMEC program and the first motions of P, SV and SH waves with their amplitude ratios. Using the location results of the main shock and aftershocks by the Anhui seismic network, combining the three-dimensional crust velocity structure imaging results of the focal region by seismic tomography, and referring on intensity distribution of the elliptic major axis' predominant direction, we conclude by comprehensive analysis that the NE-trending Susong-Zongyang fault is possibly the causative fault of the Anqing earthquake.
